CHO-SEAL 1221 1224 Conductive Elastomers
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Conductive elastomers Knitted wire mesh Conductive coatings, sealants, adhesives Cable shielding products Օ EMI/ESD shielding laminate Shielded vents and Windows TECHNICAL BULLETIN 13 CHO-SEAL® Aerospace-200 Grade Conductive Silicone CHO-SEAL® Aerospace-200 grade sheet stock materials are highly conductive elastomers which provide both RF suppression and pressure rtention. Thse materials consist of Chomerics' "essential silver" powders dispersed in silicone or fluorosilicone binders. They are r騩silient, homogeneous composites manufactured from virgin components of the highest quality, and are also available in die-cut and molded shapes. Aerospace-200 grade materials are characterized by exceptional heat stability, maintaining their electrical properties at continuous-use tempratures up to 200°C. They also meet NASA out-gassing spcifications. Variations in chemical or physical properties make each material in this grade specifically suited for certain applications. CHO-SEAL® 1221 - a fluorosilicone intended for use where solvent, oil, or jet-fuel compatibility is required. CHO-SEAL® 1224 - a m驩dium durometer silicone material. CHO-SEAL conductive elastomers are chemically inert, and will resist the effects of most corrosive atmosphres. Where pure silver-filled CHO-SEAL materials are in contact with a dissimilar mtal in a corrosive environment, coating or edge sealing of the mating surfaces may be required. (For best corrosion r詩sistance, CHO-SEAL 1285, 1298 and 1287 are recommended. Refer to Technical Bulletins 58, 19 and 18.) CHO-SEAL materials are not nutrients for fungus or microorganisms, and will not support their growth. They are mois-ture rsistant, even at high tempratures. Aerospace-200 grade sheet stock is available in standard thicknesses of 0.031 in. (0.79 mm), 0.062 in. (1.57 mm), 0.093 in. (2.36 mm) and 0.125 in. (3.18 mm); and dimensions of 10 in. x 10 in. (25.4 cm x 25.4 cm), 10 in. x 15 in. (25.4 cm x 38.1 cm), 20 in. x 15 in. (50.8 cm x 38.1 cm) and 30 in. x 20 in. (76.2 cm x 50.8 cm). Standard "D" and "O" rings, as well as extruded strips of various cross sections, are also available. Unique advantages over other methods of EMI shielding and sealing include: Heat Stability - When used with in the recommended range of continuous-use temp驩ratures, CHO-SEAL Aerospace-200 grade materials provide totally reliable shielding and sealing. Reuseability-They retain their original shape if compressed within recommended limits. Non scarring - They contain no mtal wires or knurled surfaces to break or scar mating flanges. Conformability - They conform to uneven or rough surfaces. continued

CHO-SEAL® Aerospace-200 Grade Conductive Silicone continue! SPECIFICATIONS Test CHO-SEAL CHO-SEAL Procdure 1224 1221 Type (R驩f. MIL-G-83528) Type E Type F Elastomer Binder Silicone Fluorosilicone Conductive Filler Ag Ag Volume Resistivity (ohm-cm as supplied (without psa) max.) MIL-G-83528 Para. 4.6.11 0.002 0.002 Durometer (Shore A ±5) ASTM D2240 65 75 Spcifie Gravity (±0.25) ASTM D792 3.4 4.0 Tensile Strength (psi, min.) ASTM D412 300 250 Elongation (percent, min./max.) ASTM D412 200 / 500 100/300 Tear Strength (Ib./in. min.) ASTM D624 60 40 Compression Set 70 hrs @ 100°C (percent, max.)*...